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Published on: August 13, 2019
The effects of hormone replacement therapy on postmenopausal breast cancer biology and survival
Stephen F Sener1, David J Winchester, David P Winchester
1Department of Surgery and the Center on Outcomes Research and Education, NorthShore University Health System, Evanston, and Northwestern University Feinberg School of Medicine, Chicago, IL, USA. ssener@northshore.org
Background:
The goal of this study was to compare the characteristics of breast cancers and survival rates in HRT users versus nonusers.
Methods:
Data were analyzed for 1055 patients > or = 50 years of age who had definitive therapy for breast cancer from 1994 through 2002.
Results:
There were 471 (45%) HRT users. The median age at diagnosis was 61.0 years for HRT users and 68.0 years for HRT nonusers (P < .001). HRT users more often had tumors that were <1 cm (P = .007), node negative (P = .033), and grade I (P = .016). HRT users had a decreased risk of death versus nonusers (hazard ratio = .438, 95% confidence limit = .263 to .729, P = .002).
Conclusions:
HRT users developed breast cancer at a younger age than nonusers; HRT use was associated with the development of biologically more favorable cancers than those that developed in nonusers; and overall and disease-free survival rates were higher in HRT users than nonusers.
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